I can't imagine the birds liking a sweater. Their feathers are such good insulation. Sometimes I give my birds a little cracked corn in the afternoon when I know the night will be cold. That is supposed to give them energy (lots of fat in the corn oil). They think it tastes great too.I've always read that those sweaters are bad for chickens cuz they can't fluff out their feathers??
One EE and CL molted in November so I read that it could just take time? My black sex linked molted too. Her eggs were small and bullet shaped. Maybe the break will help her eggs
Give them time. Are you adding light to keep them laying?